Japan's government says the relocation of a US military base on Okinawa island will proceed despite the re-election of a city mayor opposed to the plan.
Tokyo and Washington want to close Futenma airbase and build a new one in Henoko, in Nago city.
But Nago Mayor Susumu Inamine, who won a local election on Sunday, has vowed to block construction at the new site.
Okinawa is home to around 26,000 US troops. Many residents associate the US bases with accidents and crime.
The US and Japan first agreed to shift the Futenma Air Station from a highly-congested part of Okinawa to Nago, in the north of the island, in 1996, but the plan has been stalled amid considerable local opposition to the move.
Mr Inamine defeated the government-backed candidate, Bunshin Suematsu, by 19,839 votes to 15,684.
Speaking after his re-election on Sunday, he said the poll was about one issue - the base - and the people of Nago had spoken.
"The plan must go back to square one," he said, adding that he would "reject all procedures" linked to the relocation to Nago and deny permits for the project.
However, Japan's Defence Minister Itsunori Onodera said on Monday that the relocation would continue.
"We hope to make steady progress on the relocation plan in order to eliminate risks posed by Futenma," he said.
"It was a local election and I don't think it will immediately have a direct impact on the relocation issue," he added.
The US bases on the island form a part of its long-standing security alliance with Japan.
Last month, the Okinawa governor finally approved a landfill that will enable construction of the base - at Oura Bay, off an existing base called Camp Shwab - to start.
His decision came after the central government pledged more funds for the local economy.
Opponents have since filed a lawsuit seeking to invalidate the governor's approval.
Analysts say Mr Inamine's re-election could give momentum to the island's anti-base movement, but there could be limits to what a local mayor could do to stop the relocation.
There has been a US military presence on Okinawa since the end of World War II.